Expanding mandrel



UNITED STATES PATENT OFFICE.

HERMAN BERNER, LOUISVILLE, KENTUCKY.

EXPANDING MANDREL.

SPECIFICATION forming part of Letters Patent No. 525,645, datedSeptember 4, 1894. Application filed April 27, 1894. Serial No. 509.249.(N0 model.)

To all whom it may concern:

Be it known that I, HERMAN BERNER, of.

Louisville, in the county of Jefferson and State of Kentucky, haveinvented certain new and useful Improvements in Expanding Mandrels and Ido hereby declare the following to be a full, clear, and exactdescription of the inventlon, such as will enable others skilled in theart to which it pertains to make and use it, reference being had to theaccompanying drawlugs, which form a part of this specification.

My invention relates to improvements in expanding mandrels; and itconsists in the particular construction and arrangement of parts whichwill be fully described hereinafter and especially pointed out in theclaims. The object my invention is to provide an expanding mandrelhaving at each end tapermg sleeves which receive the expanding devicesadapted to be expanded by endwise motion over the tapering sleeves, thesaid tapering sleeves and wedges at each end extending in the samedirection so that by moving the mandrel endwise in one direction willsimultaneously loosen both sets of expanding wedges, and when forced inthe opposite direction will simultaneously tighten the same, all ofwhich will be more fully set forth hereinafter. In the accompanyingdrawings:Figure 1, 1s a longitudinal vertical section of an expandingmandrel which illustrates my invention complete. Fig. 2, is a detachedperspective view of a series of the expanding wedges. Fig. 3, is adetached perspective view of an expanding sleeve adapted to be placed onthe outside of the expanding wedges.

Referring now to the drawings, A indicates the mandrel core which isprovided at one end with the screw thread B and at the 0pposite end withan inwardly tapering sleeve 0. At the opposite end of this mandrelinside of the screw threaded portion Bis another tapered sleeve Dsimilar tothe one C,

and which extends in the same direction as is 4 clearly illustrated.Placed upon the mandrel A between the tapering sleevesO and D, is astraight sleeve J slightly larger in diameter than the diameter of theinner thicker end of the sleeve D as shown and which is provided at itsopposite end with a recess a of a proper length to permit it to passover the small inner end of the tapering sleeve 0 at the opposite end ofthe mandrel.

Placed around-each of the tapering sleeves O and D, are a series oftapering wedges E which are provided at their thickest end with groovesG, in which grooves a contracting binding spring I) is placed for thepurpose of holding the wedges normally together as shown in Fig. 2. Aswill be clearly understood when these tapering wedges are forced endwiseupon the tapering sleevesC and D they are expanded for the purpose ofengaging the inner periphery of a hub or other object which it isdesired to clamp.

Placed outside of the tapering sleeve D, is a sleeve H surrounding thescrew threaded portion B, and engaging the said screw threaded portionor the nut I. When the inner nut I is turned inward the sleeve H isforced inward engaging the thickened end of the wedges E, which in turnhave their thinnest edges engage the projecting edge of the sleeve J,thus forcing it endwise. The opposite end of this sleeve J engages thethickened end of the tapering wedges at the opposite end of the mandreland simultaneously force them endwise as will be clearly understood,thus causing the two sets of tapering wedges to simultaneously expand bythe endwise movement of the nut on the outer end of the mandrel, andthus clamp the desired object. The outer nut I is then tightened againstthe inner nut, thus locking itso that the tapering wedges are heldpermanently in the adjusted position.

I am aware that it is not new to provide a tapering expanding device ateach end of a mandrel, but in these incidents the tapers have extendedin opposite directions so that each device was separately forcedendwise, and this made it very difficult to detach the mandrel from thedevice clamped for the reason that when the mandrel was moved in onedirection it would loosen one set of expanding devices while at the sametime it tightened the other.

opposite directions requiring a separate movement for each set ofexpanding devices. 'Another great advantage in this construction is,that when it is desired to loosen the mandrel from the device clamped itis only necessary to loosen the nut I, and to tap the mandrel endwisewhen both sets of expanding devices will be simultaneously loosened fromthe object clamped and it can be removed. This it will be readilyunderstood is a great advantage over devices of this characterpreviously constructed.

The inner end of the opening made in the short sleeve H, is madetapering as shown at c for the purpose of passing over the tapered outerend of the sleeve D.

Having thus described my invention, what I claim, and desire to secureby Letters Patent, is

1. An expanding mandrel comprising a rod having two separated tapersextending in the same direction, expanding devices surrounding saidtapers, an endwise movable operative connection between and abuttingagainst the adjacent ends of said expanding devices, and a means forforcing endwise one of the said expanding devices and through the mediumof said connection the other expanding device, substantially as shownand described.

2. An expanding mandrel comprising a. shaft or red having twotaperingsleeves with their tapers extending in the same direction,

